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Veterans Of The 1st Persian Gulf War: A Study Of Medically Unexplained Symptom Models, Alexis H. Collins Sep 2010

Veterans Of The 1st Persian Gulf War: A Study Of Medically Unexplained Symptom Models, Alexis H. Collins

Loma Linda University Electronic Theses, Dissertations & Projects

In 1990-1991, shortly after the Persian Gulf War, a number of veterans began complaining about a wide range of symptoms, the most common of which were; fatigue, headache, sleep disturbance, low mood, and memory loss. These symptoms were similar to those experienced by individuals with Medically Unexplained Illnesses such as Chronic Fatigue Syndrome, Fibromyalgia, Irritable Bowel Syndrome, Multiple Chemical Sensitivity, and Somatoform Disorders. Utilizing structural equation modeling and data gathered from the Gulf War Veterans Health Questionnaire, this study attempted to determine whether symptoms experienced by veterans were best explained as individual items, discrete illnesses, or as a conglomeration of …


Facial Type Analysis Comparison Between Mri, Cbct, And Lateral Cephalometrics, Matthew A. Sanders Sep 2010

Facial Type Analysis Comparison Between Mri, Cbct, And Lateral Cephalometrics, Matthew A. Sanders

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: Single Cephalometric measurements are comparable between Cone Beam Computed Tomography (CBCT), Magnetic Resonance Imaging (MRl) and Conventional Lateral Cephalometric (LC) imaging methods. This study evaluated the agreement between the three imaging methods in facial type analysis (using a composite of 5 cephalometric measures).

Methods and Materials: Twenty-two subjects participated in this study. Cranial images were generated via three modalities: LC, CBCT and MRl. Cephalometric landmarks were identified on the three images per subject and a facial type analysis performed. An equally weighted facial type calculation composed of 5 cephalometric measurements (facial axis, facial depth, mandibular plane, lower face height, …


The Use Of The Minnesota Multiphasic Personality Inventory-Ii (Mmpi-2) In Pre-Employment Evaluations, Ana M. Gamez Sep 2010

The Use Of The Minnesota Multiphasic Personality Inventory-Ii (Mmpi-2) In Pre-Employment Evaluations, Ana M. Gamez

Loma Linda University Electronic Theses, Dissertations & Projects

Psychological testing is an important facet in the selection and hiring processes of law enforcement and public safety personnel. Research in this area suggests that the MMPI-2 scales have been correlated with problematic behavior among police officers, poor job performance, and officer misconduct. This study examined the extent to which suitability for hire could be predicted by the MMPI-2 scale L (Lie), scale K (correction), Infrequency scale (F), scale 4 Psychopathic Deviate (Pd), scale 6 Paranoia (Pa), scale 7 Psychasthenia (Pt), and scale 9 Hypomania (Ma). It examined whether profile differences emerged as a function of suitability across gender, between …


Psychological Profiles In A Female Bariatric Surgery Sample, Aimee L. Donato Sep 2010

Psychological Profiles In A Female Bariatric Surgery Sample, Aimee L. Donato

Loma Linda University Electronic Theses, Dissertations & Projects

Morbid obesity is an epidemic. Current literature suggests that people with morbid obesity tend to show increased levels of psychological dysfunction. This is especially pertinent to the clinicians who work with morbidly obese patients who seek bariatric surgery as the method for weight control. Surgery should be performed on patients who are psychologically ready to adjust to the stringent post-operative lifestyle.

The purpose of the present study was (1) to compare two groups of bariatric patients (a White group and a non-White group) on pre-surgery measures: specific scales on the Millon Behavioral Medicine Diagnostic (MBMD), the Beck Depression Inventory II …


Creating Prediction Models For Obstructive Sleep Apnea Based On Gender, Jeffrey Hwang Sep 2010

Creating Prediction Models For Obstructive Sleep Apnea Based On Gender, Jeffrey Hwang

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: Obstructive sleep apnea (OSA) is a common chronic disorder that is characterized by repetitive episodes of airflow cessation or reduction occurring during sleep as a result of partial or complete upper airway obstruction. These recurrent events have a tremendous impact on the cardiovascular system with a multitude of dangerous consequences. Numerous studies have been conducted determining etiological risk factors for OSA including anatomical predictors which have been observed with multiple imaging techniques. Cone beam computed tomography (CBCT) is a low-radiation mode of imaging that can be used to accurately identify anatomical landmarks and measure craniofacial relationships and airway dimensions. …


Microct Study Of Critical-Sized Defects Restored With A New Rhbmp-2 Carrier, Joanne S. Kim Sep 2010

Microct Study Of Critical-Sized Defects Restored With A New Rhbmp-2 Carrier, Joanne S. Kim

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: Regenerating bone in critical-sized maxillofacial osseous defects remains a challenge. The utilization of recombinant human bone morphogenetic protein-2 (rhBMP-2) to form new bone has been shown to be a promising alternative to autogenous bone grafts, and the development of a carrier matrix to effectively deliver the rhBMP-2 has been identified as the critical factor necessary for the successful clinical application of rhBMP-2. The objective of this study was to perform a microCT analysis to examine the density of reconstructed bone using different rhBMP-2 carriers in critical-sized defects.

Material and Methods: Critical-sized defects (approximately 2.5 cm) were created in the …


Mixed Effect Poisson Log-Linear Models For Clinical And Epidemiological Sleep Hypnogram Data, Bruce J. Swihart, Brian S. Caffo Phd, Ciprian Crainiceanu Phd, Naresh M. Punjabi Phd, Md Aug 2010

Mixed Effect Poisson Log-Linear Models For Clinical And Epidemiological Sleep Hypnogram Data, Bruce J. Swihart, Brian S. Caffo Phd, Ciprian Crainiceanu Phd, Naresh M. Punjabi Phd, Md

Johns Hopkins University, Dept. of Biostatistics Working Papers

Bayesian Poisson log-linear multilevel models scalable to epidemiological studies are proposed to investigate population variability in sleep state transition rates. Hierarchical random effects are used to account for pairings of individuals and repeated measures within those individuals, as comparing diseased to non-diseased subjects while minimizing bias is of importance. Essentially, non-parametric piecewise constant hazards are estimated and smoothed, allowing for time-varying covariates and segment of the night comparisons. The Bayesian Poisson regression is justified through a re-derivation of a classical algebraic likelihood equivalence of Poisson regression with a log(time) offset and survival regression assuming exponentially distributed survival times. Such re-derivation …


On Two-Stage Hypothesis Testing Procedures Via Asymptotically Independent Statistics, James Y. Dai, Charles Kooperberg, Michael Leblanc, Ross L. Prentice Aug 2010

On Two-Stage Hypothesis Testing Procedures Via Asymptotically Independent Statistics, James Y. Dai, Charles Kooperberg, Michael Leblanc, Ross L. Prentice

UW Biostatistics Working Paper Series

Kooperberg08 proposed a two-stage testing procedure to screen for significant interactions in genome-wide association (GWA) studies by a soft threshold on marginal associations (MA), though its theoretical properties and generalization have not been elaborated. In this article, we discuss conditions that are required to achieve strong control of the Family-Wise Error Rate (FWER) by such procedures for low or high-dimensional hypothesis testing. We provide proof of asymptotic independence of marginal association statistics and interaction statistics in linear regression, logistic regression, and Cox proportional hazard models in a randomized clinical trial (RCT) with a rare event. In case-control studies nested within …


Partial And Spectral-Viscosity Models For Geophysical Flows, Qingshan Chen, Max Gunzburger, Xiaoming Wang Aug 2010

Partial And Spectral-Viscosity Models For Geophysical Flows, Qingshan Chen, Max Gunzburger, Xiaoming Wang

Mathematics and Statistics Faculty Research & Creative Works

Two models based on the hydrostatic primitive equations are proposed. the first model is the primitive equations with partial viscosity only and is oriented towards large-scale wave structures in the ocean and atmosphere. the second model is the viscous primitive equations with spectral eddy viscosity and is oriented towards turbulent geophysical flows. for both models, the existence and uniqueness of global strong solutions are established. for the second model, the convergence of the solutions to the solutions of the classical primitive equations as eddy viscosity parameters tend to zero is also established. © 2010 Editorial Office of CAM (Fudan University) …


Examples Of Boundary Layers Associated With The Incompressible Navier-Stokes Equations, Xiaoming Wang Aug 2010

Examples Of Boundary Layers Associated With The Incompressible Navier-Stokes Equations, Xiaoming Wang

Mathematics and Statistics Faculty Research & Creative Works

The author surveys a few examples of boundary layers for which the Prandtl boundary layer theory can be rigorously validated. All of them are associated with the incompressible Navier-Stokes equations for Newtonian fluids equipped with various Dirichlet boundary conditions (specified velocity). These examples include a family of (nonlinear 3D) plane parallel flows, a family of (nonlinear) parallel pipe flows, as well as flows with uniform injection and suction at the boundary. We also identify a key ingredient in establishing the validity of the Prandtl type theory, i.e., a spectral constraint on the approximate solution to the Navier-Stokes system constructed by …


Virtual Manipulatives In The Classroom And Resulting Articles And Lesson Plans, Cheryl Juliana Aug 2010

Virtual Manipulatives In The Classroom And Resulting Articles And Lesson Plans, Cheryl Juliana

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Upon coming across mathematical manipulatives generated and produced by Utah State University, as a math teacher, I conducted a classroom teaching experiment in three pre-algebra classes with students of various achievement levels. After teaching the entire year using no manipulatives in the classroom, I tested my students with a general, end-of-year, core criterion, or cumulative test. Their scores were noted. The students in the study group were then given opportunities to try several manipulatives offered on the "National Library of Virtual Manipulatives," both as a class, and alone, and then retested. The following paper gives the parameters of the study, …


Spousal Concordance In Academic Achievements And Intelligence And Family-Based Association Studies Identified Novel Loci Associated With Intelligence., Yue Pan Aug 2010

Spousal Concordance In Academic Achievements And Intelligence And Family-Based Association Studies Identified Novel Loci Associated With Intelligence., Yue Pan

Electronic Theses and Dissertations

Assortative Mating, the tendency for mate selection to occur on the basis of similar traits, plays an essential role in understanding the genetic variation on academic achievements and intelligence (IQ). It is an important mechanism explaining spousal concordance. We used principal component analysis (PCA) for spousal correlation. There is a significant positive correlation between spouses by the new variable PC1 (correlation coefficient=0.515, p<0.0001). We further research the genetic factor that affects IQ by using the same data. We performed a low density genome-wide association (GWA) analysis with a family-based association test to identify genetic variants that associated with intelligence as measured by WAIS full-score IQ (FSIQ). NTM at 11q25 (rs411280, p=0.000764) and NR3C2 at 4q31.23 (rs3846329, p=0.000675) were 2 novel genes that haven't been associated with IQ from other studies. This study may serve as a resource for replication in other populations and a foundation for future investigations.


Early Stopping Of A Neural Network Via The Receiver Operating Curve., Daoping Yu Aug 2010

Early Stopping Of A Neural Network Via The Receiver Operating Curve., Daoping Yu

Electronic Theses and Dissertations

This thesis presents the area under the ROC (Receiver Operating Characteristics) curve, or abbreviated AUC, as an alternate measure for evaluating the predictive performance of ANNs (Artificial Neural Networks) classifiers. Conventionally, neural networks are trained to have total error converge to zero which may give rise to over-fitting problems. To ensure that they do not over fit the training data and then fail to generalize well in new data, it appears effective to stop training as early as possible once getting AUC sufficiently large via integrating ROC/AUC analysis into the training process. In order to reduce learning costs involving the …


A Comparative Study Between The Standards Of Learning And In-Class Grades., Randetta Lynn Fuller Aug 2010

A Comparative Study Between The Standards Of Learning And In-Class Grades., Randetta Lynn Fuller

Electronic Theses and Dissertations

We examined the Standards of Learning mathematics scores and in-class grades for a rural Virginia county public school system. We looked at third, fourth, fifth, sixth, and seventh grades as well as Algebra I, Algebra II, and Geometry classes. The purpose of this was to determine whether or not there is a strong correlation between the Standards of Learning and the students' in-class grades. Had a strong enough correlation between the Standards of Learning and in-class grades been found we would have used only the in-class grades to predict the Standard of Learning test scores. However, we found that the …


Thinking Outside The Curve, Part Ii: Modeling Fetal-Infant Mortality, Richard Charnigo, Lorie W. Chesnut, Tony Lobianco, Russell S. Kirby Aug 2010

Thinking Outside The Curve, Part Ii: Modeling Fetal-Infant Mortality, Richard Charnigo, Lorie W. Chesnut, Tony Lobianco, Russell S. Kirby

Statistics Faculty Publications

BACKGROUND: Greater epidemiologic understanding of the relationships among fetal-infant mortality and its prognostic factors, including birthweight, could have vast public health implications. A key step toward that understanding is a realistic and tractable framework for analyzing birthweight distributions and fetal-infant mortality. The present paper is the second of a two-part series that introduces such a framework.

METHODS: We propose estimating birthweight-specific mortality within each component of a normal mixture model representing a birthweight distribution, the number of components having been determined from the data rather than fixed a priori.

RESULTS: We address a number of methodological issues related to our …


A Perturbation Method For Inference On Regularized Regression Estimates, Jessica Minnier, Lu Tian, Tianxi Cai Aug 2010

A Perturbation Method For Inference On Regularized Regression Estimates, Jessica Minnier, Lu Tian, Tianxi Cai

Harvard University Biostatistics Working Paper Series

No abstract provided.


Structural Measurements For Enhanced Mav Flight, John R. Singler, Gregg Abate, Benjamin T. Dickinson Aug 2010

Structural Measurements For Enhanced Mav Flight, John R. Singler, Gregg Abate, Benjamin T. Dickinson

Mathematics and Statistics Faculty Research & Creative Works

Our sense of touch allows us to feel the forces in our limbs when we walk, swim, or hold our arms out the window of a moving car. We anticipate this sense is key in the locomotion of natural flyers. Inspired by the sense of touch, the overall goal of this research is to develop techniques for the estimation of aerodynamic loads from structural measurements for flight control applications. We submit a general algorithm for the direct estimation of distributed steady loads over bodies from embedded noisy deformation-based measurements. The estimation algorithm is applied to a linearly elastic membrane test …


Asymptotic Analysis Of The Differences Between The Stokes-Darcy System With Different Interface Conditions And The Stokes-Brinkman System, Nan Chen, Max Gunzburger, Xiaoming Wang Aug 2010

Asymptotic Analysis Of The Differences Between The Stokes-Darcy System With Different Interface Conditions And The Stokes-Brinkman System, Nan Chen, Max Gunzburger, Xiaoming Wang

Mathematics and Statistics Faculty Research & Creative Works

We consider the coupling of the Stokes and Darcy systems with different choices for the interface conditions. We show that, comparing results with those for the Stokes-Brinkman equations, the solutions of Stokes-Darcy equations with the Beavers-Joseph interface condition in the one-dimensional and quasi-two-dimensional (periodic) cases are more accurate than are those obtained using the Beavers-Joseph-Saffman-Jones interface condition and that both of these are more accurate than solutions obtained using a zero tangential velocity interface condition. the zero tangential velocity interface condition is in turn more accurate than the free-slip interface boundary condition. We also prove that the summation of the …


Roger Temam On The Occasion Of His 70th Birthday, Claude Michel Brauner, Danielle Hilhorst, Alain Miranville, Shouhong Wang, Xiaoming Wang Aug 2010

Roger Temam On The Occasion Of His 70th Birthday, Claude Michel Brauner, Danielle Hilhorst, Alain Miranville, Shouhong Wang, Xiaoming Wang

Mathematics and Statistics Faculty Research & Creative Works

No abstract provided.


A Formal Context Specific Trust Model (Ftm) For Multimedia And Ubiquitous Computing Environment, Sheikh Iqbal Ahamed, Munirul M. Haque, Nilothpal Talukder Aug 2010

A Formal Context Specific Trust Model (Ftm) For Multimedia And Ubiquitous Computing Environment, Sheikh Iqbal Ahamed, Munirul M. Haque, Nilothpal Talukder

Mathematics, Statistics and Computer Science Faculty Research and Publications

In order to ensure secure sharing of resources in an ad-hoc network of handheld devices in a multimedia and ubiquitous computing environment, mutual collaboration is essential. However, the limitations, such as poor storage and computational capability of these multimedia and ubiquitous devices stand as the bottleneck for effective sharing of resources. As a result of this drawback, the adversaries are obtaining access to the new doors for security breaches. Mutual Trust is the weapon used to combat security violations by restricting malicious devices from participating in any interaction in such an open and dynamic environment. In this paper, we present …


Noise Assumptions In Complex-Valued Sense Mr Image Reconstruction, Daniel B. Rowe, Iain P. Bruce Aug 2010

Noise Assumptions In Complex-Valued Sense Mr Image Reconstruction, Daniel B. Rowe, Iain P. Bruce

Mathematics, Statistics and Computer Science Faculty Research and Publications

In fMRI, brain images are not measured instantaneously and a volume of images can take two seconds to acquire at a low 64x64 resolution. Significant effort has been put forth on many fronts to decrease image acquisition time including parallel imaging. In parallel imaging, sub-sampled spatial frequency points are measured in parallel and combined to form a single image. Measurement time is decreased at the expense of increased image reconstruction difficulty and time. One significant parallel imaging technique known as SENSE utilizes a complex-valued regression coefficient estimation process with transposes replaced by conjugate transposes. However, in SENSE the noise structure …


Acm/Springer Mobile Networks And Applications (Monet) Special Issue On “Advanced Mobile Applications And Intelligent Multimedia Systems For Ubi-Com”, Jong Hyuk Park, Shu-Ching Chen, Mieso Denko, Sheikh Iqbal Ahamed Aug 2010

Acm/Springer Mobile Networks And Applications (Monet) Special Issue On “Advanced Mobile Applications And Intelligent Multimedia Systems For Ubi-Com”, Jong Hyuk Park, Shu-Ching Chen, Mieso Denko, Sheikh Iqbal Ahamed

Mathematics, Statistics and Computer Science Faculty Research and Publications

No abstract provided.


Estimating Teacher Effects Using Value-Added Models, Jennifer L. Green Aug 2010

Estimating Teacher Effects Using Value-Added Models, Jennifer L. Green

Department of Statistics: Dissertations, Theses, and Student Research

Value-added modeling is an alternative approach to test-based accountability systems based on the proportions of students scoring at or above pre-determined proficiency levels. Value-added modeling techniques provide opportunities to estimate an individual teacher’s effect on student learning, while allowing for the possibility to control for the effect of non-educational factors beyond a school system’s control, such as socioeconomic status. However, numerous considerations exist when using value-added models to estimate teacher effects and defining what the teacher effects really describe. Chapter 2 provides an introduction to value-added methodology by describing several value-added models available for estimating teacher effects and their respective …


An Approximate Analytical Solution Of The Fractional Diffusion Equation With External Force And Different Type Of Absorbent Term - Revisited, S. Das, R. Kumar, P. K. Gupta Aug 2010

An Approximate Analytical Solution Of The Fractional Diffusion Equation With External Force And Different Type Of Absorbent Term - Revisited, S. Das, R. Kumar, P. K. Gupta

Applications and Applied Mathematics: An International Journal (AAM)

In this article Homotopy Perturbation Method (HPM) is applied to obtain an approximate analytical solution of a fractional diffusion equation with an external force and a reaction term different from the reaction term used by Das and Gupta (2010). The anomalous behavior of diffusivity in presence or absence of linear external force due to the presence of this force of reaction term are obtained and presented graphically.


A Bayesian Approach To Dose-Response Assessment And Drug-Drug Interaction Analysis: Application To In Vitro Studies, Violeta G. Hennessey Aug 2010

A Bayesian Approach To Dose-Response Assessment And Drug-Drug Interaction Analysis: Application To In Vitro Studies, Violeta G. Hennessey

Dissertations and Theses (Open Access)

The considerable search for synergistic agents in cancer research is motivated by the therapeutic benefits achieved by combining anti-cancer agents. Synergistic agents make it possible to reduce dosage while maintaining or enhancing a desired effect. Other favorable outcomes of synergistic agents include reduction in toxicity and minimizing or delaying drug resistance. Dose-response assessment and drug-drug interaction analysis play an important part in the drug discovery process, however analysis are often poorly done. This dissertation is an effort to notably improve dose-response assessment and drug-drug interaction analysis.

The most commonly used method in published analysis is the Median-Effect Principle/Combination Index method …


Arima Model For Forecasting Poisson Data: Application To Long-Term Earthquake Predictions, Wangdong Fu Aug 2010

Arima Model For Forecasting Poisson Data: Application To Long-Term Earthquake Predictions, Wangdong Fu

UNLV Theses, Dissertations, Professional Papers, and Capstones

Earthquakes that occurred worldwide during the period of 1896 to 2009 with magnitude greater than or equal to 8.0 on the Richter scale are assumed to follow a Poisson process. Autoregressive Integrated Moving Average models are presented to fit the empirical recurrence rates, and to predict future large earthquakes. We show valuable modeling and computational techniques for the point processes and time series data. Specifically, for the proposed methodology, we address the following areas: data management and graphic presentation, model fitting and selection, model validation, model and data sensitivity analysis, and forecasting.


The Relationship Between The Level Of Support Group Participation And Psychosocial Factors In Prostate Cancer Patients Treated With Proton Therapy, Carol A. L. Davis Aug 2010

The Relationship Between The Level Of Support Group Participation And Psychosocial Factors In Prostate Cancer Patients Treated With Proton Therapy, Carol A. L. Davis

Loma Linda University Electronic Theses, Dissertations & Projects

Background. The role of support groups for cancer patients is known to be beneficial in helping people adjust to the disease, and cope with the myriad of effects that cancer has on quality of life. Although many people express interest in attending such support groups, few attend regularly. It is unclear what characteristics distinguish those who use such services from those who do not, especially among proton therapy patients.

Objective. To examine demographic and psychosocial characteristics associated with the Brotherhood of the Balloon (BOB) prostate cancer support group membership, a unique treatment-focused group originating at Loma Linda University Medical Center …


Thinking Outside The Curve, Part I: Modeling Birthweight Distribution, Richard Charnigo, Lorie W. Chesnut, Tony Lobianco, Russell S. Kirby Jul 2010

Thinking Outside The Curve, Part I: Modeling Birthweight Distribution, Richard Charnigo, Lorie W. Chesnut, Tony Lobianco, Russell S. Kirby

Statistics Faculty Publications

BACKGROUND: Greater epidemiologic understanding of the relationships among fetal-infant mortality and its prognostic factors, including birthweight, could have vast public health implications. A key step toward that understanding is a realistic and tractable framework for analyzing birthweight distributions and fetal-infant mortality. The present paper is the first of a two-part series that introduces such a framework.

METHODS: We propose describing a birthweight distribution via a normal mixture model in which the number of components is determined from the data using a model selection criterion rather than fixed a priori.

RESULTS: We address a number of methodological issues, including how the …


Principled Sure Independence Screening For Cox Models With Ultra-High-Dimensional Covariates, Sihai Dave Zhao, Yi Li Jul 2010

Principled Sure Independence Screening For Cox Models With Ultra-High-Dimensional Covariates, Sihai Dave Zhao, Yi Li

Harvard University Biostatistics Working Paper Series

No abstract provided.


A Unified Approach To Modeling Multivariate Binary Data Using Copulas Over Partitions, Bruce J. Swihart, Brian Caffo, Ciprian Crainiceanu Jul 2010

A Unified Approach To Modeling Multivariate Binary Data Using Copulas Over Partitions, Bruce J. Swihart, Brian Caffo, Ciprian Crainiceanu

Johns Hopkins University, Dept. of Biostatistics Working Papers

Many seemingly disparate approaches for marginal modeling have been developed in recent years. We demonstrate that many current approaches for marginal modeling of correlated binary outcomes produce likelihoods that are equivalent to the proposed copula-based models herein. These general copula models of underlying latent threshold random variables yield likelihood based models for marginal fixed effects estimation and interpretation in the analysis of correlated binary data. Moreover, we propose a nomenclature and set of model relationships that substantially elucidates the complex area of marginalized models for binary data. A diverse collection of didactic mathematical and numerical examples are given to illustrate …